Final Exam 2 (20%)

Question

A string p is a prefix of a string s if the leading characters of s are identical to p. For example, "abc" is a prefix of "abcde". Develop a function prefix that checks if a C string p is a prefix of another C string s.

p是s的前綴若s開頭的一段字串等於p。例如，"abc"是"abcde"的前綴。寫一個程式 判斷字串p是否字串s的前綴。

Example input 1:

abc
abcde

Example output 1:

abc is a prefix of abcde

 

Example input 2:

bc
abcde

Example output 2:

bc is not a prefix of abcde

 

Answer 1

Hidden content!
* *** * ** * *     **  
 *    *  ****     ***  *

int main()
{
**  * *  * *  **** char * *  * * 
*** * *  *******  int i,c=0;
* * * ** * ***    *  ***     *   ****** * ** * * 
    *   *  * * ** * *     * ***  ***  *** 
 * *  * **  * *** *  *   * ** ** * 
* *** ***** {
*  * **        * * *  *    ** *** ** 
* ****  *   *   *    **   ***** ** {
 ***  ** * *       * ***** * * **     *  **   **     **   *  *  ** *  **   ** 
    **   * **** ** *  *   *  * **  *** *     **  **  *** ** ** {
** * **                 **** *  ** c=0;
* *   *  * ** * * ** **   *   *      *    ***** * * **         }
*  *** *    *    * ** *  * * ** *   * *  ****   else ***  *    **** ***  *  ****   *
*      ***    *  **   **    ** ***  *    * * ******  * *  * {
  **  * *  * ***   * **      *   *   *** *   ** *    **  ** *** *     ****  ***  c++;
****  *   *** *   *****  *    * *** *  * *     ** *   * ****   }
*  *     **  **  * ** *  **  }
 *  ** ***    
   ***  * *** if(c==0)
* **    ****  *  ** ****    ** * *   *  * **      is not a prefix of   * *****   
* **       else
* ****   *   **   *  *   *** * *       *   * *   * is a prefix of **  *      **
*  * *** *   * }
 * *  **  * * return 0;
}

Comments

prog.c: In function 'main':
prog.c:8:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&a);
           ^
prog.c:9:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&b);
           ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

prog.c: In function 'main':
prog.c:10:6: warning: implicit declaration of function 'stlen' [-Wimplicit-function-declaration]
   if(stlen(b)>strlen(a))
      ^~~~~
/tmp/ccnE3ufV.o: In function `main':
prog.c:(.text+0x5b): undefined reference to `stlen'
collect2: error: ld returned 1 exit status

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Correct output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 2

Hidden content!
   **  *   *   * **   
**** **** * **** ***  ****
int main()
{
     *  *    *  *  ap;
** ****        * *  * * * ** *  ** * || ap=a)
 *   * *****  ** * ***   ** *   *   ******** * is a prefix of abcde\n");
   *****   ** ****   *
     ** * *  *  
  *    ***** * ** ***** * * ******  is not a prefix of abcde");
****  **  **  **** **       **** * *  * ** * **  ** ****   ****  *** **  * * 0;
** ** * *******   * **** * * *     *    *   ***  *** ** * ** *  ** *    
  

Comments

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

Answer 3

Hidden content!
*    ** *   *     *
**  *     ** * ******* 

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
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     *** *      *******  *** 
*    * **** **      *** * *    ****  *** ** * *  * (p[i]==s[i])
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*    * *     ******   * **   ***  **      * ***          * ***  *  **** ** * **  *****   **** **   ** * *** ***  1;
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* *  *       ** *   * * *  * *** ** ** *  *  * * **** * *  *
**  ***   *  ***    *** *** ***   * *  * * *     **** if(p[i]!=s[i])
     *** **  ** ***     * ***   *  **  *  *   * * **   *
* * **** *       ** * *    *  *** **  *    ** ***  * * ***     *         * **   * 0;
 * *  ** **** * ** * * ** *  *   **  **  ** ** *     *   *    
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}


int main()
{
****  *   **** ** 
 * **** **** * 
  **** *** ",p);
 * ***   * * **   *   * * 
****** *    ** *** 

sl=strlen(s);
pl=strlen(p);


*****  **  * && pl<sl)
{

   * *   *   **** * * ***       *** * is a prefix of %s",p,s);
}else
{
printf("%s is not a prefix of %s",p,s);
}





}

Comments

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 4

Hidden content!
#include<stdio.h>
#include<string.h>
int main()
{
* **     * *    * ** **   * *    a[99],b[99];
    int l,i;
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*  ** * ***   *  *  *  *  *  ** 
 **  *   * * **  **  * *** ** *** 
  **  *  ** *  ***   **  ** * *  *   * *
    {
 **   ** *  **   *     * * **  *  *** **  *** ****  **** **
 * * *** ***  * *****   * ** * ***  ** **   *    *
   *    * *  ***         *  *       * ** *  * *     ** * *   ** **  *  * * * * *   *  * **   ***  **   **  *   a prefix of %s",a,b);
*  * * ** * ***** *** ****   ** *  * * * *** * ** *  ** ***  **  ****   * **     
****** ** * * ** ***  *   **  ***    **       ***** 
* ********  ** * *       *   * *** * ** ***  **   **   ** **
 * * **  ** **   ***   *      ** **   *** *** *  * **
* *******     * **  *** ***  *  ***  ** * **********  *  * ***   ** *   ** *  ***    ** * **  **   **** not a prefix of %s",a,b);
 * *  * ** *   ** ** **  **      ** * * ** * *****  ** *     *     **       *  *** * **
**        *****  *  *** * * ***     * * ** ***  * 
    }


}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 5

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

int prefix(char a[100],char b[100]);


int prefix(char a[100],char b[100])
{
 ** ** *    *   * ***  ** ** i;
 ***  ******   ** **   * ** count=0;
   **  ** ** ** ******** * * len;

* ****  ****   *** ***  ** *   ****   

  * ****   ** * ** * * *** *   **  * ** 
  **  *  *      ***** * **
** * ***       **   ** *    *    **   ***   **** **  *** ***  * 
**** ** ****   * **  *  *** **   *  ** *   ** *    ***  *  * *
 * ***** *  *  ********     *   * ** * *    ** **** * *  * * **   **** * * ***  *  *  **
 *** ** ****    ***  ****   ***    *** * ** *    *  **  
**   ****** ******* ** * ** 


  *** *   *****  * * ******* *    *
    ***  *  * ****  *  *** **
*** **  ** *     *  *   *  **   *     * *****  *    *  1;
****   * *     ***  *   ** * *
** * *    **** **    ****  *

   return 0;
}


int main()
{
*  *    *  ****  *  *    a[100];
   * * *****  *   **  * ****   b[100];


*   **    **  *** ***   **** *  *******  * * *   ***  **
** ***  * **  ** **  *** **  **** * * * *** **  *   *

 *    * *  *  * * ***  *   *      *    *
    * * ** *  ** **  *******     *  ******  

 *    * ** ** *****  **  ***** * 

 {
  *  *  ** ** *****   *   *** *   * **   **     *    ** ** * **  * is a prefix of %s",a,b);
 ***   **      ** ** * * * 
 **  ***    *    ***** ****       
 ***  * * *** *** *  * 
 ** *   ****    **    ** ** **     *    **   ** * * *   *  ** ***  **   is not a prefix of %s",a,b);
 *  ** **    * *    ******


*** **   **** ******** **   *** ** 0;
}

Comments

prog.c: In function 'main':
prog.c:45:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&a);
               ^
prog.c:45:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&a);
                    ^
prog.c:46:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&b);
               ^
prog.c:46:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&b);
                    ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 6

Hidden content!
* *    *  * *** **** *
    *   **      * * *

int      *
{
   ****  **  ** *  * * * **     * * *  no idea, I * ** even do it in the  *   * **  **   *
 *  * ***  *  **      ****   * *  0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 7

Hidden content!
#include *** *   * *  **
#include ***   ** * * * 
#include    ****    * * ** *

int pref(char[],char[]);

int main(){

 *  *** ***   *  * ***     * * * p[10],s[10];
    *** *   * **   * * *   num;

  ***  ** ** ****  *  * *   * ** **  *  
  * ***       *  **   *   *** ***
 * * *****  ***** ******* ** * * **  *  ********* *
  *****   **  **** *   *** ***   * ** * * *

** *   *** ****    *      ***   = pref(p,s);

  *  **** *  ***  *    *  *   ** * *
 * **    * **  ** *  *   ***   *** **  * ****** * ** *** ***  ****  * is a prefix of %s",p,s);
*** * **  *   **** * **  **  *
 *****  *  *   *  * **  * * ****  ******  ***   * * *  **  *   is not a prefix of %s",p,s);


 return 0;
}

int pref(char p[30],char s[30]){
* ** *  * *      *  ***  i;

 * * * * ***    **    * * **  ***     *   **   ***
 **** ** *  **** *   * *** *   * * * **   *    ***** *   *      **  * *  * **   *  **** ** **   ** * *    *
**  *** **** * *****  ****    *  ** **** *  * * *** *   * * ***  * ***     ** *    ** *     * **  is a prefix of %s",p,s);
 * *  * *****  **  * * ****  *    * *   **  *** *  *
**    *  * *  ** ******* * ** *** ***  * * * ***  * ***     *******   * ****** ** **  *  *  *   *   **   is not a prefix of %s",p,s);

 *  ****  *   ** *   *  *****

}

Comments

prog.c: In function 'main':
prog.c:12:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:13:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/tmp/cc0tBG5r.o: In function `main':
prog.c:(.text+0x1f): warning: the `gets' function is dangerous and should not be used.

---

prog.c: In function 'main':
prog.c:10:13: error: stray '#' in program
     int num;#include <stdio.h>
             ^
prog.c:10:14: error: 'include' undeclared (first use in this function)
     int num;#include <stdio.h>
              ^~~~~~~
prog.c:10:14: note: each undeclared identifier is reported only once for each function it appears in
prog.c:10:23: error: 'stdio' undeclared (first use in this function)
     int num;#include <stdio.h>
                       ^~~~~
prog.c:14:1: error: expected expression before 'int'
 int pref(char[],char[]);
 ^~~
prog.c: In function 'main':
prog.c:23:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:24:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^
prog.c: In function 'main':
prog.c:51:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:52:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~

---

prog.c: In function 'main':
prog.c:14:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:15:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^

Answer 8

Hidden content!
***  ** **  **
*      **********    * 

int main()
{
         * length1, * **** c;
***      * a[100];
  *  * b[100];
*   **    d[100];

*****   *  *   * * *  ** ***  **   
*   ****  ** **    *  *   ***    ***  

* *    *   *   ** **  *

*  * **** *  ***** 

 ****  * *    ***
 * *   
 **    *** *   * **   * **   * is a prefix of     * **    *
*    * **
*** *   *    ****
  * * *  
**  **    **  ** *  * is not a prefix of  ****   ** 
   *

}

Comments

prog.c: In function 'main':
prog.c:11:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&a);
          ^
prog.c:12:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&b);
          ^
prog.c:24:11: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
           ^
prog.c:24:33: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
                                 ^

Answer 9

Hidden content!
 * * **  * * ** ***  
* *  * *   **    ** 

int main()
{
*  ** *   * * ***  * ***   *  str;
 *****  **    * *  *** * ** i, p, s;

* ** *   * *    * * *  *  * * *  * *** ****  *  &p, &s);

** **  ***** ***  * * *** (i<=0; &p; i++);
 **  * *** * ************ * ** *  *
    **    *   ** *  *  * *  **** *  *  *** * *   &p);
 *  **    *   * * * * * * **    *  * **   ****  * 
 *   * * * **  * * ** *** **
  *  ** *  *   * *** *   

 *** * ***  *  **   *  **** * *   * 0;
}

Comments

prog.c: In function 'main':
prog.c:12:7: error: expected '(' before '{' token
     if{}
       ^
prog.c:13:12: warning: too many arguments for format [-Wformat-extra-args]
     printf("abc", &p);
            ^~~~~
prog.c:14:13: warning: format '%d' expects a matching 'int *' argument [-Wformat=]
     scanf("%d");
             ^

Answer 10

Hidden content!
        ****    ** * ** *
**     * **  * ** **  
int main (){
char *   *  *
char * *      *
***    ** *  *  *   **   ***  
 ***  * * * * **      ** **  * **
*    * * **  *  ***  ****** *
**** * ** *** *****  ** * **** *   
  *** *   *** * **    
 *     * * **  is a prefix of  *  ****  ***  *   *  
}
else{
* *  * ** **  * is not a prefix of %s *** **    ** * * *
}
*  * * 0;
}

Comments

prog.c: In function 'main':
prog.c:7:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string1);
         ^
prog.c:9:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string2);
         ^